#include <iostream>
#include <vector>
#include <array>
int main()
{
	using namespace std;
	double a1[4]={1.2,2.4,3.6,4.8};
	
	vector<double> a2(4);
	a2[0]=1.0/3.0;
	a2[1]=1.0/5.0;
	a2[2]=1.0/7.0;
	a2[3]=1.0/9.0;
	
	array<double,4> a3={3.14,2.72,1.62,1.41};
	array<double,4> a4;
	a4=a3;
	
	cout<<"a1[2]: "<<a1[2]<<" at "<<&a1[2]<<endl;
	cout<<"a2[2]: "<<a2[2]<<" at "<<&a2[2]<<endl;
	cout<<"a3[2]: "<<a3[2]<<" at "<<&a3[2]<<endl;
	cout<<"a4[2]: "<<a4[2]<<" at "<<&a4[2]<<endl;
	
	a1[-2]=20.2;
	cout<<"a1[-2]: "<<a1[-2]<<" at "<<&a1[-2]<<endl;
	cout<<"a3[2]: "<<a3[2]<<" at "<<&a3[2]<<endl;
	cout<<"a4[2]: "<<a4[2]<<" at "<<&a4[2]<<endl;
	return 0;
}
